Electrical outlet box

ABSTRACT

An electrical outlet box, for mounting in an opening of a panel, includes holding members that are rotatably and slidably mounted upon a cylindrical pin fixed to the base of the housing and extending towards the open front thereof. The holding members are rotatable from an inoperative position wherein the holding member is substantially inside the housing to an operative position wherein the holding member projects through an aperture in the housing sidewall. Each holding member is slidable forwardly upon its respective pin to bear against the back side of the panel. Retention elements allow forward movement of the holding member but resist rearward movement, and guide elements guide the holding member during forward movement.

TECHNICAL FIELD

The present invention relates to improvements in electrical outletboxes.

SUMMARY OF THE INVENTION

According to the invention there is provided an electrical box formounting in an opening of a panel, including a housing having a base andsidewall(s) defining an open front to the housing with means at saidopen front for bearing against the surface of the panel surrounding theopening, the electrical outlet box further including at least twoholding members in the housing each rotatable about a respective axisextending in the front to rear direction of the housing and each havinga respective retaining flange extending sideways relative to the axis ofrotation of the member, each member being rotatable about the respectiveaxis from an inoperative position wherein the respective retainingflange is substantially inside the housing to an operative positionwherein the retaining flange projects through a respective aperture inthe housing sidewall, the holding member being slidable forwardlytowards the open front of the housing when in the operative position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear perspective view of an electrical outlet box accordingto the embodiment of the invention;

FIG. 2 is a cut-a-way front perspective view of the electrical outletbox of FIG. 1 mounted on a wall;

FIG. 3 is a perspective view of a holding member according to theembodiment of the invention; and

FIG. 4 is a front elevation of the electrical outlet box of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the invention will now be described, by way of example,with reference to the accompanying drawings.

Referring now to the drawings wherein similar numerals have been used toindicate like parts, there is shown therein an electrical outlet boxgenerally indicated at 10 according to the invention.

The electrical outlet box 10 comprises a rectangular housing 11 formedof plastics or other suitable material. The housing 11 has a rear wallor base 14 and sidewalls 15 which define an open front 16 to thehousing, the latter having a peripheral out-turned flange 12 which inuse of the dry lining box bears against the surface of a panel in whichthe housing 11 is inserted. The rear wall 14 and the two longer ones ofthe sidewalls 15 are provided with "press out" regions 18 which areattached to the housing proper by means of a number of thin walledintegral projections 19 which are easily broken to enable the regions 18to be removed to provide apertures through which electrical cables maybe inserted into the interior of the housing 11.

The housing 11 is provided with two holding members 20, which arerotatably mounted on respective cylindrical pins 30, which areintegrally formed on the rear wall 14 of the housing 11 close to twodiagonally opposed corners 31. Each holding member 20 is rotatable onits respective pin 30 through approximately 90 degrees about an axisextending in the front to rear direction of the housing 11, that is tosay, in the case of the present embodiment, about an axis at leastapproximately perpendicular to a plane containing the open front 16 ofthe housing 11. Further, the axes of rotation of the two holding members20 are themselves substantially parallel.

Each holding member 20, comprises a body portion 21 having a hollowcylindrical end 22 which engages over the respective cylindrical pin 30.A pair of oppositely directed hook-like guide members 23, are formed onthe body portion 21 and include a first part 24 which projects outwardlyfrom the body portion and a second part 25, which projects at rightangles to the first part 24, the two parts 25 extending in mutuallyopposite directions. Each holding member 20 further comprises aretaining flange or ear 26 which extends sideways relative to the axisof rotation of the member 20, i.e. approximately parallel to the planecontaining the open front 16 of the housing. Each flange 26 has tworesilient arms 27 which diverge from its free end back towards the bodyportion 21. The body portion 21 is also formed on its side opposite theflange 26 with a generally centrally disposed hollow cylindrical stock28 which is internally screw-threaded to receive a screw as will bedescribed below.

Further, the cylindrical end 22 is formed with an external protrusion 29the purpose of which will be described below.

The two opposite shorter sidewalls 15 of the housing are each providedwith an aperture 32 which is generally rectangular, but which alsoincludes two right angled slots 33, defined by a wall flange 34. Eachaperture 32 has opposite edges 35 which are substantially parallel tothe axis of rotation of the holding members 20 about the pins 30. Aswill be described, each edge 35 serves as a linear guide for arespective hook-like guide member 23. These edges 35 are bevelled andtaper (converge) from the outside surface towards the inside surface ofthe wall 15.

Each holding member 20 is rotatable about its respective pin 30 from aninoperative position wherein the respective retaining flange 26 isinside the housing (see member 20 at the top left hand side in FIG. 4)to an operative position wherein the retaining flange 26 projectsthrough the respective aperture 32 in the housing sidewall 15 (seemember 20 at right hand side in FIG. 4). When in the inoperativeposition the protrusion 29 bears against the inside surface of theadjacent wall 15 so that the holding member is firmly held in thisposition and this bearing force must be manually overcome to move themember to the operative position as will now be described.

To move it from its inoperative position to its operative position theholding member 20 is rotated clockwise about its pin 30 towards therespective aperture 32, initially to a position in which lips 36 at theend of each resilient arm 27 engage on the inside of the housing 11 withthe edges 35 of the aperture 32. At this point a greater force must beused to compress the arms 27 slightly towards one another to enable thearms 27 to pass through the aperture 32 and permit the holding member 20to be pushed fully home to its operative position, as shown for theright hand member 20 in FIG. 4. In the fully home operative position thelips 36 on the free ends of the arms 27 now bear resiliently against thebevelled edges 35 of the aperture 32, and the guide members 23, projectthrough the right-angled lower ends of slots 33. In this position theholding members 20 may be slid forward towards the front 16 of thehousing 11.

During such forward sliding movement the hook-like guide members 23,which were brought into alignment with the edges 35 by the rotation ofthe member 20 into the operative position, engage the opposite edges 35of the aperture 32, see FIG. 1. Thus the member 20 is stablised duringthe forward sliding movement by the guide members 23 near the bottom andthe arms 27 at the top, which both engage the edges 35 of the aperture32. Further, the positive engagement of the hooks 23 with the edges 35prevent the holding member 20 from being inadvertently rotated back intothe housing 11 when in a forward position.

In use, the electrical outlet box 10 is fitted to structure, for examplea "stud wall" 40 as generally indicated in FIG. 2. The electrical outletbox 10 provides a housing for accommodating an electrical socket intowhich a plug from an electrical appliance may be inserted. A stud wallnormally comprises two panels of, for example, plasterboard which aresecured together by means of wooden laths which are spaced apart, sothat the wall is essentially hollow.

In order to fit the electrical outlet box 10 into the stud-wall, arectangular aperture (not shown) is cut in the panel 40 which is of asize of approximately that of the housing 11.

The housing 11 is then inserted into the aperture in the panel 40 withthe holding members 20 in their non-operative positions and the twoholding members 20 are then rotated to their operative position. Theholding members are then moved forward so that the flange 12 abuts thefront surface of the panel 40 and the locking flange 26 abuts the rearsurface of the panel 40.

A conventional electrical socket (not shown) is mounted in the housing11 and is connected to electrical cables which enter the housing throughthe apertures formed when the flanges 18 are removed. A cover plate (notshown) is then located on the front of the housing 11, and screws engagein the stock 28 from the cover plate. As the screws are tightened, theholding members 20, 20' are pulled forward so that the locking flange 26securely grips the rear surface of the panel 40, and the flange 12 gripsthe front surface of the panel 12.

Clearly, while the fitter is attempting to locate the screws in thestocks 28, there is a possibility that the holding element 20 as a wholemay be pushed back rearwardly into the housing 11 once again, out ofreach of the screw. To prevent this, the body portion 21 of each holdingmember 20 is provided on its outer surface with two rearward facingwedge-shaped projections 41. As the holding element 20 is slid forward(upwards in FIG. 1) these projections 41 will "ratchet" across the freeedge 42 of the flange 34, and resist the holding member 20 sliding backin the rearward direction beyond a certain point. However, because ofthe direction of angle of the projections 41 they do permit forwardsliding movement of the holding member. Of course, the holding member 20can be pushed fully back by slight deformation of the holding member 20and/or the flange 34 so that the edge 42 of the flange 34 clears theprojections 41.

In order to remove the electrical outlet box 10 from the panel 40, thecover plate must be removed and the holding members 20, 20' moved totheir non-use position inside the housing 11 so that the locking flanges26 no longer grip the panel 40.

What is claimed is:
 1. An electrical outlet box for mounting in anopening of a panel, including a housing having a base and sidewall(s)defining an open front to the housing with means at said open front forbearing against the surface of the panel surrounding the opening, theelectrical outlet box further including at least two holding members inthe housing each comprising a body portion rotatably mounted upon arespective cylindrical pin fixed to the base of the housing andextending towards the open front thereof and a retaining flangeextending sideways from the body substantially parallel to the openfront of the housing, each member being rotatable about the axis of therespective pin from an inoperative position wherein the respectiveretaining flange is substantially inside the housing to an operativeposition wherein the retaining flange projects through a respectiveaperture in the housing sidewall, each holding member being slidableforwardly on its respective pin towards the open front of the housingwhen in the operative position.
 2. An electrical outlet box as claimedin claim 1, wherein the housing has a linear guide which issubstantially parallel to the axis of rotation of its respective holdingmember, and each of the holding member has a guide means which isbrought into alignment with the linear guide by rotation of the memberinto the operative position and which engages the linear guide duringforward sliding of the member.
 3. An electrical outlet box as claimed inclaim 2, wherein the linear guide comprises an edge of the respectiveaperture and wherein the guide means comprises a hook.
 4. An electricaloutlet box as claimed in claim 3, wherein each holding member has meansfor cooperation with the housing which permits forward sliding movementof the member but resists rearward sliding movement of the member.
 5. Anelectrical outlet box as claimed in claim 4, wherein the means forcooperation comprises at least one wedge-shaped projection whichcooperates with said edge of the respective aperture.
 6. An electricaloutlet box as claimed in claim 1, wherein the housing is substantiallyrectangular, the apertures are provided in respective opposite sidewallsof the housing and the pins are located adjacent opposite diagonalcorners of the housing, wherein each of the holding members may berotated from the inoperable position, wherein the body portion liesalong the inside surface of the respective sidewall at a right angle toone of the other sidewalls containing one of the apertures, to theoperative position, wherein the body portion lies along the insidesurface of one of the respective sidewalls containing one of theaperture with the flange projecting through said one of the apertures.7. An electrical outlet box as claimed in claim 6 wherein each holdingmember has a pair of mutually outwardly directed hooks on the same sideof the body portion as the flange, and wherein each aperture hasopposite parallel edges which are substantially perpendicular to theopen front of the housing but spaced apart less than the distancebetween the furthest extremities of the hooks, each aperture furtherhaving mutually outwardly directed portions remote from the open frontof the housing to permit the hooks to pass through said one of therespective sidewalls containing said one of the apertures when themember is rotated from the inoperative position to the operativeposition with the hooks aligned with the outwardly directed portions,the hooks engaging the parallel edges of the respective aperture duringforward sliding of the member.
 8. An electrical outlet box as claimed inclaim 7, wherein each holding member has at least one wedge-shapedprojection on the same side of the body as the flange and the at leastone projection cooperates with a lower edge of the respective apertureto permit forward sliding movement of the member but resist rearwardsliding of the member.